Even vinyl-loving skeptics who insist that an iPad app could never really replace the tactile thrill of interacting with a physical album will have to reconsider after a few minutes of playing with undun, the Roots’ companion app to the group’s forthcoming album of the same name. This thing is gorgeous.

Björkaside, usually, band apps are kind of rote — maybe you get a few concert or press release pics of them jamming out; maybe there’s a lyrics tab and a chance to stream some live video or audio, plus a prominently-placed shopping cart. undun has some of those things, but it’s a lot more about making the concept album’s concept pop off the record, so you forge a deeper and more personal connection to the material.

The app uses three main components to create this connection: First, there’s “The Redford Stephens Documentary,” a series of six video clips that tell the story of undun’s fictional protagonist via interviews with friends and family, interspersed with music videos for four of the album’s fourteen tracks. Then there’s the lyrics tab, which is fairly standard for these things, but an important part of an app designed to elucidate a concept album. Finally, there’s a collection of rich black-and-white photographs, ostensibly of Stephens and his Philadelphia home. These look great on the iPad, though they may get lost a bit on the iPhone or iPod Touch. It’d also fill most iPads to capacity pretty quickly –- at nearly half a gigabyte, undun is massive, but quality doesn’t come quick, and it’s a small price to pay. Oh, and for a limited time, it’s free. [Download the app via iTunes.]